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41.
42.
Mitsuomi?Shimazakimitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" title="MS mitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Hiromitsu?Endo Mamoru?Yabe 《Ichthyological Research》2004,51(2):120-125
Halieutopsis bathyoreos Bradbury, 1988 (Lophiiformes: Ogcocephalidae), previously described only on the basis of the holotype (62.6mm in standard length) from the central North Pacific, is redescribed on the basis of the holotype and six additional specimens (41.2–68.7mm in standard length) collected from the western South Pacific, off Papua New Guinea, and the western North Pacific, including the Japanese Archipelago. Halieutopsis bathyoreos is distinguished from its congeners by having a shelflike rostrum extending anteriorly well beyond the mouth, a dorsal escal lobe slightly bisected ventrally, an illicial cavity square in outline and completely visible in ventral view, and lacking tubercles on the ventral surface of the disk. The following characters are newly added to the diagnoses of this species: rostrum width 21–29% of head length, tubercles on the dorsal surface of the disk about half the diameter of those on the lateral margin, and 13–15 large lateral-line scales on the tail. 相似文献
43.
The purpose of this research was to improve the solubility and therefore dissolution and bioavailability of triamterene, a
poorly water soluble diuretic, by complexation with β-cyclodextrin. Triamterene has been reported to show low bioavailability
after oral administration, with wide intersubject variation. This study presents the formulation of solid dispersions of triamterene
with β-cyclodextrin—by cogrinding, kneading, and coevaporation, using low pH conditions—and their characterizations, evaluation
of improvement in dissolution profiles, and in vivo advantage. Phase solubility studies indicated complex with possible stoichiometry
of 1∶1 and a stability constant of 167.67M−1. The solid dispersions were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, x-ray diffraction,
and differential scanning calorimetry studies. The characterization studies confirmed inclusion of the phenyl ring of triamterene
within the nonpolar cavity of β-cyclodextrin in the coevaporate. Remarkable improvement in in vitro drug release profiles
in 0.1 N HCl and pH 6.8 phosphate buffer was observed with all dispersions, especially the coevaporate. The coevaporate, when
administered orally in rats, also exhibited improved in vivo activity, as measured by net sodium ion excretion, as compared
with triamterene powder. Thus, coevaporation of the drug and β-cyclodextrin from acidified alcohol provide the optimum condition
for inclusion complexation to give a binary system with remarkable improvement in in vitro drug release profile and in vivo
performance. 相似文献
44.
NMR solution structure of attractin,a water-borne protein pheromone from the mollusk Aplysia californica 总被引:1,自引:0,他引:1
Garimella R Xu Y Schein CH Rajarathnam K Nagle GT Painter SD Braun W 《Biochemistry》2003,42(33):9970-9979
Water-borne protein pheromones are essential for coordination of reproductive activities in many marine organisms. In this paper, we describe the first structure of a pheromone protein from a marine organism, that of attractin (58 residues) from Aplysia californica. The NMR solution structure was determined from TOCSY, NOESY, and DQF-COSY measurements of recombinant attractin expressed in insect cells. The sequential resonance assignments were done with standard manual procedures. Approximately 90% of the 949 unambiguous NOESY cross-peaks were assigned automatically with simultaneous three-dimensional structure calculation using our NOAH/DIAMOD/FANTOM program suite. The final bundle of energy-refined structures is well-defined, with an average rmsd value to the mean structure of 0.72 +/- 0.12 A for backbone and 1.32 +/- 0.11 A for heavy atoms for amino acids 3-47. Attractin contains two antiparallel helices, made up of residues Ile9-Gln16 and I30-S36. The NMR distance constraints are consistent with the three disulfide bonds determined by mass spectroscopy (C4-C41, C13-C33, and C20-C26), where the first two could be directly determined from NOESY cross-peaks between CH beta protons of the corresponding cysteines. The second helix contains the (L/I)(29)IEECKTS(36) sequence conserved in attractins from five species of Aplysia that could interact with the receptor. The sequence and structure of this region are similar to those of the recognition helix of the Er-11 pheromone of the unicellular ciliate Euplotes raikovi, suggesting a possible common pathway for intercellular communication of these two distinct pheromone families. 相似文献
45.
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47.
Bernstein BW Painter WB Chen H Minamide LS Abe H Bamburg JR 《Cell motility and the cytoskeleton》2000,47(4):319-336
The ADF/cofilin (AC) proteins are necessary for the high rates of actin filament turnover seen in vivo. Their regulation is complex enough to underlie the precision in filament dynamics needed by stimulated cells. Disassembly of actin by AC proteins is inhibited in vitro by phosphorylation of ser3 and pH<7.1. This study of Swiss 3T3 cells demonstrates that pH also affects AC behavior in vivo: (1) Wounded cells show pH-dependent AC translocation to alkaline-induced ruffling membrane; (2) The Triton extractable (soluble) ADF from Swiss 3T3 cells decreases from 42+/-4% to 23+/-4% when the intracellular pH (pH(i)) is reduced from 7.4 to 6.6; (3) Covariance and colocalization analyses of immunostained endogenous proteins show that ADF partitions more with monomeric actin and less with polymeric actin when pH(i) increases. However, the distribution of cofilin, a less pH-sensitive AC in vitro, does not change with pH; (4) Only the unphosphorylatable AC mutant (A3), when overexpressed as a GFP chimera, uniquely produces aberrant cellular phenotypes and only if the pH is shifted from 7.1 to 6.6 or 7.4. A mechanism is proposed that explains why AC(A3)-GFP and AC(wt)-GFP chimeras generate different phenotypes in response to pH changes. Phospho-AC levels increase with cell density, and in motile cells, phospho-AC increases with alkalization, suggesting a homeostatic mechanism that compensates for increased AC activity and filament turnover. These results show that the behavior of AC proteins with pH-sensitivity in vitro is affected by pH in vivo. 相似文献
48.
The release of DNA 5'-terminal deoxyribose-phosphate residues from enzymatically incised apurinic/apyrimidinic sites by human cell extracts has been under investigation. During the course of these studies, we observed that ataxia telangiectasia cell extracts modify deoxyribose-phosphate (dRp) residues by converting them to an altered form, dRp-X, which shows altered chromatographic properties on HPLC analysis. The chemical nature of the adduct is as yet unknown, but dRp-X is stable to both heat and acid. The modification requires an enzymatic activity and a low-molecular weight co-factor. Extracts of normal cells contain a dialyzable inhibitor that suppresses the reaction occurring with ataxia telangiectasia cell extracts. Formation of dRp-X has been observed in 7 out of 7 ataxia telangiectasia lymphoblastoid lines which represent at least 3 genetic complementation groups. Similar modification of dRp did not occur with extracts of cells of normal origin, nor those representing Fanconi's anaemia, xeroderma pigmentosum, Bloom's syndrome, Werner's syndrome or Friedreich's ataxia. 相似文献
49.
Iana H. Haralambieva Scott D. Painter Richard B. Kennedy Inna G. Ovsyannikova Nathaniel D. Lambert Krista M. Goergen Ann L. Oberg Gregory A. Poland 《PloS one》2015,10(3)
Background
Although influenza causes significant morbidity and mortality in the elderly, the factors underlying the reduced vaccine immunogenicity and efficacy in this age group are not completely understood. Age and immunosenescence factors, and their impact on humoral immunity after influenza vaccination, are of growing interest for the development of better vaccines for the elderly.Methods
We assessed associations between age and immunosenescence markers (T cell receptor rearrangement excision circles – TREC content, peripheral white blood cell telomerase – TERT expression and CD28 expression on T cells) and influenza A/H1N1 vaccine-induced measures of humoral immunity in 106 older subjects at baseline and three timepoints post-vaccination.Results
TERT activity (TERT mRNA expression) was significantly positively correlated with the observed increase in the influenza-specific memory B cell ELISPOT response at Day 28 compared to baseline (p-value=0.025). TREC levels were positively correlated with the baseline and early (Day 3) influenza A/H1N1-specific memory B cell ELISPOT response (p-value=0.042 and p-value=0.035, respectively). The expression and/or expression change of CD28 on CD4+ and/or CD8+ T cells at baseline and Day 3 was positively correlated with the influenza A/H1N1-specific memory B cell ELISPOT response at baseline, Day 28 and Day 75 post-vaccination. In a multivariable analysis, the peak antibody response (HAI and/or VNA at Day 28) was negatively associated with age, the percentage of CD8+CD28low T cells, IgD+CD27- naïve B cells, and percentage overall CD20- B cells and plasmablasts, measured at Day 3 post-vaccination. The early change in influenza-specific memory B cell ELISPOT response was positively correlated with the observed increase in influenza A/H1N1-specific HAI antibodies at Day 28 and Day 75 relative to baseline (p-value=0.007 and p-value=0.005, respectively).Conclusion
Our data suggest that influenza-specific humoral immunity is significantly influenced by age, and that specific markers of immunosenescence (e.g., the baseline/early expression of CD28 on CD4+ and/or CD8+ T cells and T cell immune abnormalities) are correlated with different humoral immune response outcomes observed after vaccination in older individuals, and thus can be potentially used to predict vaccine immunogenicity. 相似文献50.
EC Costa A Moreira B Cavalcanti K Krinski MS Aoki 《Biology of sport / Institute of Sport》2015,32(1):35-40
The present study investigated the effect of unilateral and bilateral resistance exercise (RE) on maximal voluntary strength, total volume of load lifted (TVLL), rating of perceived exertion (RPE) and blood lactate concentration of resistance-trained males. Twelve healthy men were assessed for the leg extension one-repetition maximum (1RM) strength using bilateral and unilateral contractions. Following this assessment, an RE session (3 sets of repetitions to failure) was conducted with bilateral and unilateral (both limbs) contractions using a load of 50% 1RM. The TVLL was calculated by the product of the number of repetitions and the load lifted per repetition. RPE and blood lactate were measured before, during and after each set. Session RPE was measured 30 minutes after RE sessions. There was a significant difference in the bilateral (120.0±11.9) and unilateral (135.0±20.2 kg) 1RM strength (p < 0.05). The TVLL was similar between both RE sessions. Although the repetitions decreased with each successive set, the total number of repetitions completed in the bilateral protocol (48) was superior to the unilateral (40) protocol (p < 0.05). In both bouts, RPE increased with each subsequent set whilst blood lactate increased after set 1 and thereafter remained stable (p < 0.05). The RPE and lactate responses were not significantly different between both sessions. In conclusion, a bilateral deficit in leg extension strength was confirmed, but the TVLL was similar between both RE sessions when exercising to voluntary fatigue. This outcome could be attributed to the number of repetitions completed in the unilateral RE bout. The equal TVLL would also explain the similar perceptual and metabolic responses across each RE session. 相似文献